Elke Goethe, Martina Ackermann, Larissa Bulmann, Kristin Laarmann, Astrid Lewin, Janita Luehrs, Mathias Muesken, Ralph Goethe
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引用次数: 0
Abstract
Zinc is the second most abundant transition metal in living cells and is involved in numerous biological processes. Regulation of Mycobacterium smegmatis (MSMEG) zinc homeostasis and zinc-specific importers ZnuABC and ZnuABC2 in the mycobacterial cytoplasmic membrane are well described; however, transport across the outer membrane (OM) remained unexplored so far. MspD is a porin highly similar to MspA, the major and well-studied porin responsible for the uptake of several compounds. Unlike MspA and the paralogues MspB and MspC, MspD was found to be transcriptionally induced upon zinc starvation and deletion of the global Zinc Uptake Regulator ZUR. Our study aimed to investigate the role of mspD (msmeg_6057) in MSMEG zinc homeostasis as well as the regulation of MspD expression. In addition, by growth experiments, quantitative real-time PCR analyses, in situ gene tagging and electron microscopy, we successfully demonstrated the zinc-responsive expression of the MspD protein as well as its complex formation and incorporation into the OM. Overall, the results provided strong evidence for an involvement of the MspD protein in zinc homeostasis of MSMEG.
期刊介绍:
We publish high-quality original research on bacteria, fungi, protists, archaea, algae, parasites and other microscopic life forms.
Topics include but are not limited to:
Antimicrobials and antimicrobial resistance
Bacteriology and parasitology
Biochemistry and biophysics
Biofilms and biological systems
Biotechnology and bioremediation
Cell biology and signalling
Chemical biology
Cross-disciplinary work
Ecology and environmental microbiology
Food microbiology
Genetics
Host–microbe interactions
Microbial methods and techniques
Microscopy and imaging
Omics, including genomics, proteomics and metabolomics
Physiology and metabolism
Systems biology and synthetic biology
The microbiome.